SPI_cursor_parse_open
SPI_cursor_parse_open — set up a cursor using a query string and parameters
Synopsis
Portal SPI_cursor_parse_open(const char *name, const char *command, const SPIParseOpenOptions *options)
Description
SPI_cursor_parse_open sets up a cursor (internally, a portal) that will execute the specified query string. This is comparable toSPI_prepare_cursor followed bySPI_cursor_open_with_paramlist, except that parameter references within the query string are handled entirely by supplying aParamListInfo object.
For one-time query execution, this function should be preferred overSPI_prepare_cursor followed bySPI_cursor_open_with_paramlist. If the same command is to be executed with many different parameters, either method might be faster, depending on the cost of re-planning versus the benefit of custom plans.
Theoptions->params object should normally mark each parameter with thePARAM_FLAG_CONST flag, since a one-shot plan is always used for the query.
The passed-in parameter data will be copied into the cursor's portal, so it can be freed while the cursor still exists.
Arguments
const char *namename for portal, or
NULLto let the system select a nameconst char *commandcommand string
const SPIParseOpenOptions *optionsstruct containing optional arguments
Callers should always zero out the entireoptions struct, then fill whichever fields they want to set. This ensures forward compatibility of code, since any fields that are added to the struct in future will be defined to behave backwards-compatibly if they are zero. The currently availableoptions fields are:
ParamListInfoparamsdata structure containing query parameter types and values; NULL if none
intcursorOptionsinteger bit mask of cursor options; zero produces default behavior
boolread_onlytruefor read-only execution
Return Value
Pointer to portal containing the cursor. Note there is no error return convention; any error will be reported viaelog.